A Divide-and-Conquer Approach to Dicke State Preparation

We present a divide-and-conquer approach to deterministically prepare Dicke states |Dkn> (i.e. equal-weight superpositions of all n-qubit with Hamming Weight k) on quantum computers. In an experimental evaluation for up n=6 qubits IBM Quantum Sydney and Montreal devices, we achieve significantly higher state fidelity compared previous results [Mukherjee et.al. TQE'2020, Cruz QuTe'2019]. The gains are achieved through several techniques: Our circuits first divide the weight between blocks n/2 qubits, then conquer those improved versions unitaries [Brtschi FCT'2019]. Due sparse connectivity IBM's heavy-hex-architectures, these implemented linear nearest neighbor topologies. Further in (estimating) due our use measurement error mitigation hardware progress.